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• The five-element high-entropy alloy is synthesized by arc-discharging approach. • Hollow and yolk-shell structures are obtained after the oxidation process. • The microstructural evolution in oxidation process is uncovered. • Exchange bias effect is observed in the oxidized nanoparticles. High-entropy alloys (HEAs) have attracted extensive attention ascribed to their unique physical and chemical properties induced by the cocktail effect. However, their oxidation behaviors, in particular at nanoscale, are still lack because of multi-element complexity, which could also be completely different from the bulk counterparts. In this work, we synthesized FeCoNiTiCu five-element HEA nanoparticles(NPs) with uniform elemental distribution by arc-discharging approach, and further investigated their oxidation behaviors at 250 °C, and 350 °C. The morphology, structure and element distribution of NPs were analyzed by transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and electron energy loss spectroscopy (EELS). The surface oxidation in FeCoNiTiCu NPs during the high-temperature process can induce nanoscale pores at core/shell interfaces by Kirkendall effect, and even the eventual coalescence into a single cavity. Additionally, the oxidation states of NPs with diameters (d) varying from 60 to 350 nm were analyzed in detail, revealing two typical configurations: hollow (d < 150 nm) and yolk-shell structures (d > 150 nm). The experimental results were complemented by first-principles calculations to investigate the diffusion behaviors of five elements, evidencing that the surface oxidation strongly alters the surface segregation preferences: (1) in the initial stage, Cu and Ni appear to prefer segregating on the surface, while Co, Ti and Fe tend to stay in the bulk; (2) in the oxidation process, Cu prefers to stay in the center, while Ti segregates to the surface ascribed to the reduced potential energies. The study gives new insights into oxidation of nanoscale HEA, and also provides a way for fabrication of high-entropy oxides with controllable architectures. [Display omitted] [ABSTRACT FROM AUTHOR]

Phase equilibria of the Fe –Co –R system with R ⩽ 33.3 at.% Sm0.5Nd0.5were determined in an isothermal section at 1073 K and a vertical section RFe2–RCo2by using optical microscopy, X-ray diffraction analysis, electron probe microanalysis, and differential thermal analysis techniques. There are seven intermetallic phases: (Sm, Nd) (Fe, Co)2, (Sm, Nd)(Fe, Co)3, (Sm, Nd)5(Fe, Co)17, (Sm, Nd)2(Fe, Co)7, (Sm, Nd)5(Fe, Co)19, (Sm, Nd)(Fe, Co)5, and (Sm, Nd)2(Fe, Co)17. The (Sm, Nd)5(Fe, Co)17phase dissolves less than 4 at.% Co at 1073 K. However, the (Sm, Nd)2(Fe, Co)7phase in R2(Fe1–xCox)7alloys dissolves about 15 at.% Fe at 1073 K.

In this study, an interval-parameter chanced-constrained full-infinite programming (ICFP) model based on Monte Carlo simulation is proposed for supporting water quality management under uncertainty (expressed as interval parameters, probability distribution, and functional intervals), and analyzing the reliability of satisfying (or the risk of violating) various constraints. The ICFP model was applied to investigate the utility of the model for managing industry development under water quality constraints in the Ankang section of the Hanjiang River Basin, which faces threats of point and nonpoint source pollution. The research area is one of the water sources of the South-to-North Water Diversion, which is a national strategic project aimed at mitigating the water shortage in north and northwest China. The results indicated that higher discharge amounts of chemical oxygen demand occur at the medicine manufacturing industry. Tradeoffs between economic benefits and system-failure risks were also examined. Alternative policy can be obtained from different combinations of decision variables within their lower and upper bounds, which are valuable for decision makers, who need to develop the desired regional economic plans while satisfying environmental requirements.

For making accurate assessment about each characteristics paramete of three-dimensional surface micro-topography, mathematic model for the datum plane of three-dimensional surface micro-topography assessment was established with least squares method, the relational expression of the average fitting error and maximum error were made. The datum plane equation was found by processing experimental data with least squares fitting method. The rationality and feasibility of the algorithm which is used to establish datum plane were verified through error calculation and analysis of the datum plane equation. The research provides the foundation for parametric assessment of 3D surface micro-topography and provides a method for datum surface establishment of curved surface.

There are many factors that affect the safety and reliability of large winding hoist’s cylinder shell structure，and most of them are of more or less randomness，But,in the reliability analysis of tube shell structure, For factors on the tube shell vary from degrees of structural failure. Therefore, It is of great significance to study the size of the various factors that affect the reliability of the tube shell structure. In this paper, the large winding hoist cylinder shell reliability sensitivity were calculated and analyzed using the latest achievements of reliability sensitivity calculation. The results show that，the mean square deviation of strength ( ) and stress ( ) are larger, the tube shell structure becomes more insecure, and the strength ( ) to tube failure rate of the shell structure is getting much larger than the stress ( ). The intensity ( ) on the tube shell is greater than stress ( ) on the impact of structural failure， respective proportion is 82.24% and 17.76%. we will strictly control the intensity’s change in designing, manufacturing and using of large winding hoist cylinder shell structure, and As far as possible to the direction of the large fluctuations; For the stress( ), will as far as possible so that the direction to small fluctuations. This theoretical research and practical calculation of the structure have a larger theoretical significance and practical value in studying hoist cylinder shell structure on design, manufacture and use.

In this paper, a system was introduced, which bases on Flame Cutter NC System and software platform of LabVIEW which the USA NI company developed. Composing of NC machine, partition of modules and assignments, functions confirming, data processing of machining and control, structure of software by the numbers and realization method of two CPUs. The system makes use of multitasking of LabVIEW to make the programmer realize easily the task, which is difficulty to acquire in in tradition programme. It is a kind of comparatively convenient and swift thinking to realize system interface and multitasking by the platform of LabVIEW.

Due to the complexity of machine tool thermal errors affected by various factors, a new combining prediction model, based on the theory of gery system GM (1,1) model, is applied to the trend prediction of machine tool thermal errors. The degree of smoothness of primary data sequence is first improved by function transform method and sequentially grey system GM (1,1) model is established; second, time series analysis model is established by remnant sequence of GM (1,1) model to amend the precision of grey system GM (1,1) model. Thus, the precision of combining prediction model is further improved. Through the prediction study on thermal error modeling in a spot NC turning center, testing results showed that combining prediction model can highly improve machine tool’s prediction precision and make it more effective for real-time compensation of machine tool thermal error.

Abstract:: Using a two-parameter wave function, we calculate variationally the binding energy of an exciton bound to an ionized donor impurity (D+,X) in GaAs-AlxGa1-xAs quantum wells for the values of the well width from 10 to 300 Å, when the dopant is located in the center of the well and at the edge of the well. The theoretical results confirm that the previous experimental speculation proposed by Reynolds et al. [Phys. Rev. B 40, 6210 (1989)] is the binding energy of D+,X for the dopant at the edge of the well. In addition, we also calculate the center-of-mass wave function of the exciton and the average interparticle distances. The results are discussed in detail.

Abstract:: The experimental data on the interactions of 10.6A GeV gold nuclei in nuclear emulsions are analyzed with particular emphasis of target separation interactions and study of critical exponents. Charged fragment moments, conditional moments as well as two and three – body asymmetries of the fast moving projectile particles are determined in terms of the total charge remaining bound in the multiply charged projectile fragments. Some differences in the average yields of helium nuclei and heavier fragments are observed, which may be attributed to a target effect. However, two and three-body asymmetries and conditional moments indicate that the breakup mechanism of the projectile seems to be independent of target mass. We looked for evidence of critical point observable in finite nuclei by study the resulting charged fragments distributions. We have obtained the values for the critical exponents γ, β and τ and compare our results with those at lower energy experiment (1.0A GeV data). The values suggest that a phase transition like behavior, is observed.

Starch from mung bean (Vigna radiata) was isolated and some of the important characteristics determined. The yield of starch was 31.1% on a whole-seed basis. The shape of the starch granule was oval to round to bean shaped, with granules 7–26 μm in diameter. Scanning electron micrographs revealed the presence of smooth surfaces. The gelatinization temperature range was 58–67–82°C and the enthalpy of gelatinization was 18.5 J/g. The total amylose content was 45.3%, of which 12.1% was complexed by native lipids. The X-ray diffraction pattern was of the ‘C’ type and the X-ray intensities were much stronger than in other legume starches. The starch exhibited a high swelling factor ( 43.6 at 95°C) in water. The viscoamylographic examination of the starch paste (6% w/v) showed the absence of a peak viscosity, a low 95°C viscosity [200 Brabender units (BU)], an increase in consistency ( 140 BU) during the holding cycle at 95°C and a set-back of 220 BU. Native granules were readily hydrolyzed by porcine pancreatic α-amylase (76.4% in 72 h). Retrogradation of mung bean starch (as measured by changes in syneresis, gel strength, enthalpy and X-ray diffraction intensities) appeared to be more severe than in other legume starches.

A quasi-flow comer theory of elastic—plastic finite deformation of ductile materials has been proposed. By introducing a decreasing function of quasi-elastic modulus with respect to strain into the classical flow theory and normality law and by modifying the common decomposition of elastic-plastic strain rate, the present quasi-flow comer theory achieves smooth and continuous transitions from the normality law (the Prandtl-Reuss equation) to the non-normality law with strain, and from plastic loading to elastic unloading. On isotropic condition, the J2flow and deformation theories can be included as special cases of the quasi-flow corner theory. The proposed theory is then applied to simulate the instability and deformation localization under plane strain tension and uniaxial tension of anisotropic sheet metals. Some of the numerical results have been compared with experimental ones.

Using emulsion detectors a transverse-momentum analysis of projectile fragments has been performed in Au induced nuclear interactions at 11.6 A GeV/c. Evidence for collective flow of the projectile fragments has been obtained. Angular distributions of the principal vectors of projectile and target fragments have shown strong azimuthal correlation.

The decomposition of acetic acid on a Rh(110) single crystal has been studied using molecular beam reaction spectroscopy and temperature-programmed desorption (TPD). It was found that on all clean and coadsorbate predosed surfaces the first step of the reaction was the decomposition of the acid to hydrogen and acetate. On the clean surface the decomposition will go further to produce CO₂, carbon, and hydrogen. However, on carbon-, nitrogen-, or oxygen-predosed surfaces the acetate is stabilised to different extents. The reasons for the stabilisation effects are discussed, and a few structural sources are described. A "surface explosion" was observed with the acetate decomposed on the coadsorbate precovered surfaces.Copyright 1993, 1999 Academic Press

Abstract.: The complete charge distribution of products from Au nuclei fragmenting in nuclear emulsion at 10.7A GeV has been measured. Multiplicities of produced particles and particles associated with the target source are used to select peripheral and central events. A statistical analysis, based on event-by-event charge distributions, show that a population of subcritical, critical and supercritical events, i.e. a phase transition like behaviour, is observed among peripheral collisions.

We investigated how agonist‐induced patterned rises in cytosolic Ca2+ concentration ([Ca2+]i) regulate exocytotic secretion in the rat pancreatic acinar cell. The distribution of [Ca2+]i was visualized with a confocal microscope, which revealed that a Ca2+ ionophore, A23187, induced slow and homogeneous [Ca2+]i rises, while acetylcholine (ACh) always triggered primary Ca2+ spikes at the granular area which bears secretory granules. Secretion was monitored by measuring capacitance with the patch clamp method. Errors in the estimates of membrane capacitance (C) due to changes in conductance (G) were experimentally as well as theoretically evaluated to be one‐tenth of the actual signals. We found that A23187 raised G without changing C at a low concentration, while it triggered asynchronous rises in G and C with lags in C, at a high concentration. By contrast, ACh triggered simultaneous rapid rises in G and C. Our results support the hypothesis that exocytotic secretion is less sensitive to Ca2+ than to ion channels and is directly caused by agonist‐induced primary Ca2+ spikes at the granular area. It is therefore suggested that spatio‐temporal patterns of Ca2+ oscillations could play a key role in exocytotic secretion from the exocrine acinar cell.

In the present study, we analyzed the effects of Glycyrrhizapolysaccharide (GCP) on growth performance, serum antioxidant capacity, and biochemistry of broilers. A total of 600, one-day-old AA broilers randomly divided into 5 treatment groups with 6 replicate pens of 20 birds per cage received dietary supplementation with GCP (0, 200, 500, 1,000, and 1,500 mg/kg) for 42 d. The supplementation of GCP linearly decreased (P< 0.05) feed conversion rate on day 22 to 42. Dietary supplementation with GCP reduced (P< 0.05) serum total cholesterol on day 21 and 42 and linearly improved (P< 0.05) albumin and high-density lipoprotein cholesterol. Dietary supplementation with 1,000 or 1,500 mg/kg GCP significantly increased (P< 0.05) serum total superoxide dismutase (T-SOD) activity on day 21 and 42 and reduced (P< 0.05) serum malondialdehyde content on 21 d. Dietary supplementation with 1,000 or 1,500 mg/kg GCP significantly improved (P< 0.05) interleukin-1β (IL-1β) and interferon-γ (IFN-γ) expressions in liver on day 21 and 42. At the end of the experiment, we randomly selected 20 broilers from 3 treatment groups (0, 1,000, and 1,500 mg/kg), respectively, to perform an lipopolysaccharide (LPS)-induced acute stress experiment. The 60 broilers were divided into 6 treatment groups with 10 birds per cage. The experiment was designed as a 3 × 2 factorial arrangement with GCP (0, 1,000, or 1,500 mg/kg) and LPS (injection of saline or 1 mg/kg body weight) levels as treatments. When the grouping was finished, the broilers were immediately intraperitoneally injected with LPS or normal saline. Six hours after challenged, serum antioxidant and liver immunity were analyzed. The results showed that dietary GCP prevented LPS-induced reductions in T-SOD activity and increases in malonaldehyde content (P< 0.05). Also, dietary GCP supplementation mitigated the LPS-induced increase in IL-1β and IFN-γ in the liver. Supplementation with 1,500 mg/kg GCP showed the most optimal effect in broilers. GCP has the potential to be used as feed additive in broilers.

A new class of DC-free error-correcting convolutional codes is presented. The codes are constructed based on error-correcting convolutional codes and can be encoded and decoded using convolutional encoders and decoders with slight modifications. The DC-free error correcting codes are especially well suited for applications in high-speed noisy channels.

The lentivector is the most efficient tool for transgenesis among those currently available as it possesses the ability of transducing both inviding and nondividing (quiescent) cells, including stem cells. However, to achieve such a goal, highly infectious viral particles must be made and handled properly. That is the two key steps to which attention should be paid to. For the first aspect, high titer of the proviral particles, or virons, is achieved by good packing. For the second, freezing and thawing should be avoided as much as possible as the particles are extremely susceptible to the cycle. We conducted packing ourselves to ensure that almost all the packing cells were transduced. To use the particles to the most of their capacity, we used them as fresh/soon as possible or within a week or cryo-preserved them in small aliquots. In transgenesis, approximately 100% and 90% of transfection of cells were achieved in vitro and in vivo respectively. The transgenes were inherited to the next generation as GPF was observed in the sections of the testes, organs, fetus and lambs, and the transgene was detected by RT-PCR, Western blot and Southern blot.(poster)